The present technology relates to an error detection and correction unit, an error detection and correction method, an information processor, and a program allowing, when executed by a computer, the computer to implement an error detection and correction method in the error detection and correction unit. More specifically, the present technology relates to an error detection and correction unit, an error detection and correction method, and an information processor each of which uses a plurality of kinds of encoding systems, and a program allowing, when executed by a computer, the computer to implement an error detection and correction method in the error detection and correction unit.
When data stored in a data recording and reproduction unit such as a magneto-optical recording disk, a hard disk, and a non-volatile memory is reproduced, the stored data may be corrupted and may not be read correctly, due to damage to the data recoding and reproduction unit, thermal noise, and the like. To deal with such data corruption, a typical data recording unit encodes data that is to be stored into an error detection and correction code (ECC), and holds the ECC. When the data is reproduced, the data recoding unit is allowed to detect and correct an error in the data with use of the ECC.
In encoding, a plurality of encoding systems may be used to improve error correction capability. For example, there is proposed a non-volatile memory that encodes a plurality of data into block code words, encodes these respective block code words into respective convolution code words, and then holds the convolution code words (for example, refer to Japanese Unexamined Patent Application Publication No. 2010-287305). In a case where the non-volatile memory has performed error correction to each of the block code words, and the error correction to one of the block code words has failed, the non-volatile memory reliably corrects an error in the data by decoding the convolution code word containing the block code word to which the error correction has failed.